The purpose of this research is to study the genetic polymorphisms in blood and other tissues in order to obtain information about: 1) the effects of structural alteration on molecular function; 2) the effects of such molecular functional changes on overall physiology; 3) the applicability of genetic variants to mapping the human chromosomes and other uses of genetic markers; 4) the association between apparently benign molecular variation and susceptibility to disease. Methods used include electrophoretic and chromatographic separation of proteins, histochemical staining of enzymes, blood group serological testing, immunodiffusion and immunoelectrophoretic procedures, and radioisotope measurements of labelled blood components.